Various aircraft are being designed to use electric starter generators (S/G) rather than air turbine starters to start the engines. These S/Gs can generate significant heat during start and need to be cooled. One way to cool S/Gs is to use fan flow, but if fan flow is not available (such as during a ground start), fuel may be used to provide cooling during start. An S/G cooling system must be able to control the fuel flow used for cooling. During engine start, one of the conventional ways to turn flow on and off in the S/G cooling system is through the use of a solenoid valve. However, this can be relatively expensive, heavy, and can consume significant electrical power.
Accordingly, there is a need for a simple S/G cooling system that can provide S/G cooling during engine starting without the use of a solenoid valve. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.